"Top secret" documents submitted to and approved by the secret Foreign Intelligence Surveillance Court that overseas U.S. intelligence agencies reveal wide-reaching orders that allow the NSA to utilize information "inadvertently" collected from communications in the U.S. without a warrant, the Guardian's Glenn Greenwald reports.

It is the UK newspaper's latest exclusive report on the U.S. government's surveillance programs.

A building on the National Security Administration (NSA) campus is seen on Thursday, June 6, 2013, in Fort Meade, Md. The Obama administration on Thursday defended the National Security Agency's need to collect telephone records of U.S. citizens, calling such information "a critical tool in protecting the nation from terrorist threats." Credit: AP

The Guardian explains:

The Guardian is publishing in full two documents submitted to the secret Foreign Intelligence Surveillance Court (known as the Fisa court), signed by Attorney General Eric Holder and stamped 29 July 2009. They detail the procedures the NSA is required to follow to target "non-US persons" under its foreign intelligence powers and what the agency does to minimize data collected on US citizens and residents in the course of that surveillance.

The documents show that even under authorities governing the collection of foreign intelligence from foreign targets, US communications can still be collected, retained and used.

The procedures cover only part of the NSA's surveillance of domestic US communications. The bulk collection of domestic call records, as first revealed by the Guardian earlier this month, takes place under rolling court orders issued on the basis of a legal interpretation of a different authority, section 215 of the Patriot Act.

The Fisa court's oversight role has been referenced many times by Barack Obama and senior intelligence officials as they have sought to reassure the public about surveillance, but the procedures approved by the court have never before been publicly disclosed.

The documents published by the Guardian show that data collected on "U.S. persons" under the foreign intelligence authority must be destroyed. They also reveal the steps analysts are required to take to check targets that are outside the U.S. and how U.S. call records are used to help remove U.S. citizens and residents from data collection.

But the provisions approved by the Fisa court also reportedly allow the NSA to do the following:

• Keep data that could potentially contain details of US persons for up to five years;

• Retain and make use of "inadvertently acquired" domestic communications if they contain usable intelligence, information on criminal activity, threat of harm to people or property, are encrypted, or are believed to contain any information relevant to cybersecurity;

• Access the content of communications gathered from "U.S. based machine[s]" or phone numbers in order to establish if targets are located in the US, for the purposes of ceasing further surveillance.

Greenwald argues the broad scope of the court orders "clashes" with claims made by President Obama's and other U.S. intelligence officials that the NSA is unable to access Americans' data without first obtaining a warrant.

Further, seemingly lining up with claims made by NSA whistleblower Edward Snowden, the top secret documents suggest that analysts many times have full discretion to determine who is actually targeted under the NSA's foreign surveillance powers. However, a percentage of targeting decisions are "reviewed by internal audit teams on a regular basis," Greenwald adds.

The Guardian published two separate top secret documents that were submitted to the Fisa court. Read document one here, and document two here.